When using a multi-aperture imaging system to view a distant object, undesirable noise caused by the radiation emitted by various elements and structures in the telescope (i.e., near field radiation) can obscure the signal of interest by the time it reaches the image plane of the imaging system. This is particularly true in the infrared region of the electromagnetic spectrum, as the elements of imaging systems tend to emit relatively large amounts of near field radiation in this region.
One approach to reducing the noise contributed by near field radiation is to aggressively cool the imaging system elements, thereby reducing the radiation they give off in the infrared region of the spectrum. The cooling systems used in this approach are undesirably expensive and heavy, increasing the launch costs and operational complexity of space-based telescopes. Despite the best efforts at cooling such imaging systems, their signal-to-noise ratio (SNR) is still limited by the noise contribution of near field radiation.
Accordingly, there is a need to reduce the noise contribution of near field radiation in multi-aperture imaging systems. The present invention satisfies this need and provides other advantages as well.